Seal for pressurized dispensing apparatus

ABSTRACT

A resilient seal is interposed between a cyclical dispenser and the pressurized container for the material to be dispensed, and all surfaces are sealed to prevent loss of pressurized gas or the material to be dispensed.

O Unlted States Patent 1191 1111 3,817,431 Kempton June 18, 1974 SEAL FOR PRESSURIZED DISPENSING v 3,273,610 9/1966 Frost 222/402.13 x

APPARATUS 3,666,144 5/1972 Winder 222/70 [76] Inventor: William G. Kempton, 1855 g gz g 'g gd Newport Primary ExaminerStanley H. Tollberg Assistant ExaminerLarry H. Martin [22] Filed: .July 19, 1972 [21] Appl. No.: 273,175

[52] US. Cl. 222/542, 222/394 [57] ABSTRACT [51] Int. Cl Bd 83/14 53 Fi f Search 222 52 173 1 A resilient seal is interposed between a cyclical dis- -222 394 40213 504 542 penser and the pressurized container for the material 1 to be dispensed, and all surfaces are sealed to prevent 5 References Cited loss of pressurized gas or the material to be dispensed.

UNITED STATES PATENTS 2,772,034 11/1956 Richmond 222/542 x 6 Claims, 2 Drawing Figures we we /0 95 w 2 I a Z5 g5 33' A? SEAL FOR PRESSURIZED DISPENSING APPARATUS BACKGROUND OF THE INVENTION There exist various dispensers forpressurized fluids, such as aerosol cans of insecticide, air fresheners, and the like, wherein a pressurized can is snapped onto a dispenser and the dispensing valve of the can is held open to allow the flow of material to be dispensed from the can and through thevalve chamber of a solenoid or other dispenser valve which is cyclically operated by clock-works or by an electrically operated circuit which periodically energizes a solenoid for opening the dispensing valve. When the cyclically operated valve is closed, the dispensing valve chamber is under pressure derived from the pressurized can or receptacle, and there is a tendency towards leakage of the material between the opposing surfaces of the can and the dispenser and around the dispensing stem of the can or receptacle, due to the fact that the stem and the internal valve in the can are constantly held in an open condition.

The result of such leakage, in addition to undesired loss of fluid, is that the dispenser is contaminated and becomes dirty and unsightly. Obviously, the loss of the fluid to be dispensed or the propellant results in the need for changing receptacles more often than would be necessary if a good seal is maintained.

In addition, when the dispensing stem of the receptacle is held constantly open for a period of time, there is a tendency for the stem to stick in the open position, so that removal of the receptacle for purposes of changing the receptacle may result in the uncontrolled discharge of the residual material and propellant from the receptacle or can.

SUMMARY or THEINVENTION The present invention provides a seal for preventing loss of material from a pressurized receptacle having a valved stem which is held open to allow the material to be dispensed from a dispenser base.

In addition, the seal of the invention provides means for gripping the dispenser stern of the receptacle and pulling it to the closed position when the receptacle is removed from the dispenser base.

In accomplishing the foregoing, a resilient seal member is interposed between the can and the dispenser and has pressure sealing engagement therewith, as well as sealing engagement with the dispenser stem.

This invention possesses many other advantages, and has other purposes which may be made more clearly apparent from a consideration of a form in which it may be embodied. This form is shown in the drawings accompanying and forming part of the present specification. It will now be described in detail, for the purpose of illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a diagrammatic vertical section through an aerosol dispenser incorporating the seal of the invention which is shown in elevation; and

FIG. 2 shows, in vertical section, a representative seal of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT The dispenser 10 comprises a housing 11, preferably of plastic, the top side of which carries an upstanding socket 12 around which the top of an aerosol can. when inverted, may engage on a peripheral bead l3. Typically, the aerosol can C has a bead engaging flange 13a and a central island 13b from which a dispenser stem 13c projects, so as to be normally manually depressible. In the present case, the island 13b engages a top seal S, later to be described, cooperating with the can and preventing the escape of fluid. A conduit 16 passes from the seal S into a valve assembly 17 through which the pressurized fluid is to be dispensed.

The valve assembly 17 comprises a valve member in the form of a steel cylindrical piston 18 which is a loose fit within a cylindrical chamber 19 provided by a brass cylinder 20. The ends of the chamber 19 are provided with end plugs 21, 22 which are suitably affixed in the cylinder 20. The cylinder 20 is surrounded by a solenoid coil 23 housed within an outer steel case 24 including steel end washers 24a, 24b. The piston 18 constitutes the'solenoid armature.

The solenoid coil 23, case 24 and'washers 24a, 24b are held in assembly within the housing 11 by means of a plastic sleeve 246 which at one end is threaded, as at 24d, to an annular internal flange 24a. At its other end, the sleeve 24c has an internal flange 24f which engages the outer periphery of a retainer washer 24g which engages at its inner periphery the adjacent end of the cylinder 20.

The conduit 16 communicates with the chamber 19 in the cylinder 20 via an aperture or passage which is circumscribed by a protruding valve seat 25 on the plug 21. A similar oppositely disposed, protruding valve seat 26 is provided in the lower plug 22 and circumscribes a discharge passage 27. The piston 18 carries resilient valve head elements 28, 29 in its upper and lower faces, respectively, for alternately engaging the valve seats, and thereby form an upper and lower valve. Passage 27 in the plug 22 leads from the lower valve seat 26 to a tube 30 which passes out of the housing 11 and carries a spray nozzle 31.

The valve assembly, thus far described, will be recognized as a dispensing valve of the type which allows the inflow of a measured quantity of pressurized fluid from the aerosol can C, through the passage 16, into the chamber 19 when the valve head 28 is off of its seat, as shown, and the valve head 29 is on its seat. The volume of liquid is determined by the difference between the volume of the chamber 19 and the volume of the piston or armature 18. When the piston or armature 18 is shifted to its alternate position, opening valve seat 26 and closing valve seat 25, the pressurized fluid will be discharged to the atmosphere through conduit 30 and nozzle 31.

Timing means are provided to cyclically energize the solenoid coil 23 to effect such shifting of the piston or armature l8, momentarily, to the dispensing position. At all other times, the pressure of fluid in the chamber will hold the piston or armature in the position shown. The mass of the piston assures contact between the valve head 29 and the seat 26. In the illustrative application of the valve, the means for cyclically energizing the solenoid coil 23 is enclosed within the housing 11.

Within the housing 11 is a suitable battery 32 for energizing the solenoid coil 23 and a timing circuit 33 preferably comprising a printed circuit board for controlling the connection from the battery 32 to the coil 23, is also enclosed in the housing 11. The timing circuit 33 includes a variable resistor 34 controlled by knob 35 on the housing for varying the interval between successive actuation of the coil 23. The printed circuit board, without requiring further illustration, may advantageously comprise a typical capacitorresistor timing circuit (not shown) which is charged by the battery 32, and the discharge cycle of which is varied by the potentiometer or variable resistor 34, whereby the solenoid coil is periodically instantaneously energized to shift the armature 18, as is well known.

The seal S is adapted to prevent the loss of fluid to be dispensed or propellant between the plug 21 and the island 13b, andaround the stem 130.

More particularly, as seen in FIG. 2, the seal S includes an axially extended body 40 having an upper end surface 41 and a lower end surface 42 which have a normal, uncompressed spacing greater than the distance from the end surface 41c of the island 13b and an upwardly facing end surface 21b of the plug 21 when the can C is in place on the bead 13. Extending vertically through the body is a central hole 43, the diameter of which, in the undeformed state, is slightly less than the outside diameter of the dispenser stem 13c. Between the ends 41 and 42 of the body is an outwardly projecting circumferential flange 44 having upper and lower horizontal surfaces 45 and 46, respectively, which are vertically spaced, in an uncompressed condition, a distance greater than the clamped up dimension between a downwardly facing surface 47 on a clamping ring 48, which is clamped in the neck 12 by the body 24c and washer 24g, and an upwardly facing surface 49 on the plug 21. Thus, when the can C is applied to the neck 12, the dispenser stem 13c is frictionally and sealingly engaged in the opening 43 of the seal S, and the seal body is deformed endwise between the can island 13b, about the stem 13c, and the wall 21b of the plug 21, to prevent the undesired flow of material from the stem, either upwardly through the opening 43 and outwardly between the sealing surfaces 41, 410, or from the stem 13c outwardly between the sealing surfaces 21b, 42.

In the illustrative form, moreover, sealing contact between the stem 13c and the wall of the opening 43 is assured, even though tolerances might otherwise impairproper sealing contact. In this connection, beneath the seal flange 44, the seal body is tapered at 50 and is disposed in a tapered hole 51 in the plug 21, so that the body portion 50 will be deformed radially inwardly into sealing engagement with the stem 13c in response to endwise compression between the opposing can and plug surfaces 410 and 21b.

As will now be apparent, all surfaces between which fluid has a tendency to flow from the stem 13c are effectively resiliently sealed to prevent leakage. In addition, when a can is removed from the dispenser base, the resilient gripping of the stem 13c will cause it to be pulled outwardly from the can to a normal, closed condition, so that the fluid cannot exhaust from the can in an uncontrolled manner.

I claim:

1. In dispensing apparatus comprising a dispenser base having dispensing valve means, said base having means for mounting thereon a pressurized receptacle containing a fluid to be dispensed, said receptacle having a dispenser stem held in a dispensing position when said receptacle is mounted on said base, and means releasably interlocking saidreceptacle to said base, the improvement wherein a resilient seal is provided between said receptacle and said base, said receptacle and said base having opposed surfaces held in positions compressively deforming said resilient seal by said interlocking means, said stem extending through said seal and being surrounded thereby and including means sealingly connecting said seal to said base.

2. In dispensing apparatus as defined in claim 1, said resilient seal being resiliently deformed into sealing engagement with said stem.

3. In dispensing apparatus as defined in claim 1, said base and said seal having interengaged tapered portions for deforming said resilient seal into engagement with said stem.

4. In dispensing apparatus as defined in claim 1, said resilient seal comprising an elongated body having a central opening receiving said stem, said opening having a normal diameter less than the outside diameter of said stem.

5. In dispensing apparatus as defined in claim 1, said resilient seal comprising an elongated body, said means sealingly connecting said seal to said base including an outwardly projecting flange on said body, and means on said base providing opposed surfaces clamping said flange.

6. In dispensing apparatus as defined in claim 1, said resilient seal comprising an elongated body, said means sealingly connecting said seal to said base including an outwardly projecting flange on said body, and means on said base providing opposed surfaces clamping said flange, said body having a central opening receiving said stem, said base and said body having interengaged tapered portions deforming said body into sealing engagement with said stem. 

1. In dispensing apparatus comprising a dispenser base having dispensing valve means, said base having means for mounting thereon a pressurized receptacle containing a fluid to be dispensed, said receptacle having a dispenser stem held in a dispensing position when said receptacle is mounted on said base, and means releasably interlocking said receptacle to said base, the improvement wherein a resilient seal is provided between said receptacle and said base, said receptacle and said base having opposed surfaces held in positions compressively deforming said resilient seal by said interlocking means, said stem extending through said seal and being surrounded thereby and including means sealingly connecting said seal to said base.
 2. In dispensing apparatus as defined in claim 1, said resilient seal being resiliently deformed into sealing engagement with said stem.
 3. In dispensing apparatus as defined in claim 1, said base and said seal having interengaged tapered portions for deforming said resilient seal into engagement with said stem.
 4. In dispensing apparatus as defined in claim 1, said resilient seal comprising an elongated body having a central opening receiving said stem, said opening having a normal diameter less than the outside diameter of said stem.
 5. In dispensing apparatus as defineD in claim 1, said resilient seal comprising an elongated body, said means sealingly connecting said seal to said base including an outwardly projecting flange on said body, and means on said base providing opposed surfaces clamping said flange.
 6. In dispensing apparatus as defined in claim 1, said resilient seal comprising an elongated body, said means sealingly connecting said seal to said base including an outwardly projecting flange on said body, and means on said base providing opposed surfaces clamping said flange, said body having a central opening receiving said stem, said base and said body having interengaged tapered portions deforming said body into sealing engagement with said stem. 